Wednesday 30 December 2009 15.27 EST
First published on Wednesday 30 December 2009 15.27 EST

The US is planning retaliatory strikes in Yemen against al-Qaida over its attempt to blow up a transatlantic flight on Christmas Day.

American officials say intelligence efforts are focused on identifying and tracking down those who plotted to put Umar Farouk Abdulmutallab on the plane with enough explosive in his underwear to bring down the Northwest Airlines flight from Amsterdam. But they warn that finding those responsible is unlikely to be swift and say that identifying other "high-value" al-Qaida targets for retaliatory attack would also be a priority.

"First we have to find out who put Abdulmutallab on the plane with the bomb," said a US official working alongside intelligence organisations. "He's providing some leads and we're not dealing with an unknown quantity here. We've been watching and listening to what goes on in Yemen and we may have pieces of the puzzle already and just need to fit it together.

"If and when we identify them then we plan how to deal with them. Who they are is one thing, where they are is another.If they're still in Yemen and we can get a lock on them then it won't be too difficult to know what to do. But they know who they are and won't be standing out. After that we can move with the president's authorisation. I don't think there's much doubt that authorisation will be forthcoming, but no one should think all of this is going to happen overnight."

The official acknowledged that there was likely to be political and public pressure on Barack Obama to strike back at al-Qaida, particularly with Republican opponents breaking with the usual solidarity on national security issues to accuse him of weakness and making America vulnerable to attack.

"The people we want are the ones who put Abdulmutallab on the plane. Until we can get them there are other high-value targets that will make the point that attacking America does not go unpunished," said the official.

But given the regular attacks against al-Qaida in Yemen, these may have a greater impact on American public opinion than on the extremist group.

The US has been conducting a covert assault with drone attacks on al-Qaida bases for about a year, while CIA agents inside the country help direct ground operations. American special forces have been training the Yemeni military and may have been involved in raids.

General David Petraeus, the American regional commander, and John Brennan, the president's counterterrorism adviser, both visited Yemen this year.

Joe Lieberman, chairman of the Senate's homeland security committee, who visited Yemen in August, described the country this week as a focus of the assault on al-Qaida. "Yemen now becomes one of the centres of that fight. We have a growing presence there – and we have to – of special operations, Green Berets, intelligence," he said.

Yesterday, Yemeni forces targeted Nasser Ahmed al-Ahdal, a former prisoner released after renouncing violence but believed to have renewed links to al-Qaida. One man was injured and captured but Ahdal and two others escaped.

Several al-Qaida members killed in raids by Yemeni forces in the past fortnight had been released or had escaped from prison. Others who have left jail to rejoin the fight include Nasser al-Wahayshi, the Yemeni leader of al-Qaida, who escaped along with 22 others from prison in Yemen in 2006. His deputy, Saeed al-Shihri, joined al-Qaida in Yemen last year after being released to Saudi Arabia from Guantánamo.

While intelligence officials plan how to hit back abroad, they are under pressure at home after Obama blamed intelligence failings for Abdulmutallab being allowed to board a plane to the US.

The president has ordered that a preliminary report be delivered to him today tomorrow explaining how the young Nigerian managed to smuggle the explosives on to the flight.

The criticism is focused on the CIA and the national counterterrorism centre (NCC) established after 9/11. The CIA is under scrutiny because it picked up intelligence from Yemen that a Nigerian was involved in a forthcoming attack at about the same time that Abdulmutallab's father told US diplomats in the Nigerian capital, Abuja, that his son had become radicalised in Yemen and was a possible threat. That information was shared with CIA officials in Abuja who passed it on to the NCC, but it was apparently not matched with the intelligence from Yemen. On Tuesday Obama condemned the failure to share information and other intelligence failings as "totally unacceptable".